Discussion

Arthraxon hispidus is native to Asia, but is naturalized and spreading along roadsides, shores, ditches and in low woods and fields of the eastern United States. It is also naturalized in Mexico, Central America, and the West Indies. Plants in the Flora region belong to A. hispidus (Thunb.) Makino var. hispidus, the most widespread and variable of the four varieties. Arthraxon castratus (Griff.) V. Naray. ex Bor reported from Puerto Rico, differs from A. hispidus in having pilose lemma margins, a palea in its second floret, and three anthers.